Remove registered_lints field from Session

It only exists to pass some information from one part of the driver to
another part. We can directly pass this information to the function that
needs it to reduce the amount of mutation of the Session.

4 files changed, 8 insertions, 9 deletions

diff --git a/compiler/rustc_driver_impl/src/lib.rs b/compiler/rustc_driver_impl/src/lib.rs
index 2e01c385a66..b8d5281087e 100644
--- a/compiler/rustc_driver_impl/src/lib.rs
+++ b/compiler/rustc_driver_impl/src/lib.rs
@@ -350,6 +350,8 @@ fn run_compiler(
 
     callbacks.config(&mut config);
 
+    let registered_lints = config.register_lints.is_some();
+
     interface::run_compiler(config, |compiler| {
         let sess = &compiler.sess;
         let codegen_backend = &*compiler.codegen_backend;
@@ -365,7 +367,7 @@ fn run_compiler(
         // `--help`/`-Zhelp`/`-Chelp`. This is the earliest it can run, because
         // it must happen after lints are registered, during session creation.
         if sess.opts.describe_lints {
-            describe_lints(sess);
+            describe_lints(sess, registered_lints);
             return early_exit();
         }
 
@@ -982,7 +984,7 @@ the command line flag directly.
 }
 
 /// Write to stdout lint command options, together with a list of all available lints
-pub fn describe_lints(sess: &Session) {
+pub fn describe_lints(sess: &Session, registered_lints: bool) {
     safe_println!(
         "
 Available lint options:
@@ -1086,7 +1088,7 @@ Available lint options:
 
     print_lint_groups(builtin_groups, true);
 
-    match (sess.registered_lints, loaded.len(), loaded_groups.len()) {
+    match (registered_lints, loaded.len(), loaded_groups.len()) {
         (false, 0, _) | (false, _, 0) => {
             safe_println!("Lint tools like Clippy can load additional lints and lint groups.");
         }
diff --git a/compiler/rustc_interface/src/interface.rs b/compiler/rustc_interface/src/interface.rs
index 07ae24ee6d3..7ad893f61ab 100644
--- a/compiler/rustc_interface/src/interface.rs
+++ b/compiler/rustc_interface/src/interface.rs
@@ -479,7 +479,6 @@ pub fn run_compiler<R: Send>(config: Config, f: impl FnOnce(&Compiler) -> R + Se
             let mut lint_store = rustc_lint::new_lint_store(sess.enable_internal_lints());
             if let Some(register_lints) = config.register_lints.as_deref() {
                 register_lints(&sess, &mut lint_store);
-                sess.registered_lints = true;
             }
             sess.lint_store = Some(Lrc::new(lint_store));
 
diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs
index 160525cead0..9f6106f9cfb 100644
--- a/compiler/rustc_session/src/session.rs
+++ b/compiler/rustc_session/src/session.rs
@@ -156,9 +156,6 @@ pub struct Session {
     /// This only ever stores a `LintStore` but we don't want a dependency on that type here.
     pub lint_store: Option<Lrc<dyn LintStoreMarker>>,
 
-    /// Should be set if any lints are registered in `lint_store`.
-    pub registered_lints: bool,
-
     /// Cap lint level specified by a driver specifically.
     pub driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
 
@@ -1068,7 +1065,6 @@ pub fn build_session(
         prof,
         code_stats: Default::default(),
         lint_store: None,
-        registered_lints: false,
         driver_lint_caps,
         ctfe_backtrace,
         miri_unleashed_features: Lock::new(Default::default()),
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index a384c286039..5d82b8e309a 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -846,11 +846,13 @@ fn main_args(
 
     let config = core::create_config(input, options, &render_options, using_internal_features);
 
+    let registered_lints = config.register_lints.is_some();
+
     interface::run_compiler(config, |compiler| {
         let sess = &compiler.sess;
 
         if sess.opts.describe_lints {
-            rustc_driver::describe_lints(sess);
+            rustc_driver::describe_lints(sess, registered_lints);
             return;
         }